Process for sulfurized olefinic product

Abstract

A process for preparing, in high yield, a sulfurized olefinic product for use in lubricating oil compositions having a low chlorine content, a sulfur content of from about 40 to about 50 weight percent and a viscosity at 100° C. of less than about 20 cSt.

What is claimed is: 
     
       1. A process for preparing, in high yield, a sulfurized olefinic product having a chlorine content of less than about 2000 ppm and a sulfur content of more than about 30 weight percent comprising: a) contacting an adduct of a sulfur halide and an olefin with a sulfur source in an alkaline aqueous medium comprising water and a lower alkanol at a temperature of from about 20° to 100° C. said alkanol having a boiling point of greater than about 85° C. to thereby form a mixture having an aqueous phase containing alcohol and water and an organic phase containing a sulfurized olefinic product; and   b) heating the organic phase to form, in high yield, the sulfurized olefinic product having a chlorine content of less than about 2000 ppm.   
     
     
       2. The process of claim 1 wherein the temperature of the mixture formed in step a) is in the range of from about 90° C. to reflux. 
     
     
       3. The process of claim 1 wherein the sulfur source is S, or NaHS, or S and NaHS. 
     
     
       4. The process of claim 1 wherein the lower alkanol is n-propanol, or a mixture of n-propanol and t-butanol. 
     
     
       5. The process of claim 3 wherein the molar ratio of NaHS to adduct is in the range of from about 1.3:1 to about 1.5:1. 
     
     
       6. The process oft claim 3 wherein the molar ratio of S to adduct is in the range of from about 0.05:1 to about 0.3:1. 
     
     
       7. The process of claim 3 wherein the molar ratio of NaHS to adduct is in the range of from about 1.3:1 to about 1.5:1 and the ratio of S to adduct is in the range of from about 0.05:1 to about 0.3:1. 
     
     
       8. The process of claim 7 wherein the lower alkanol is n-propanol or a mixture of n-propanol and t-butanol, and wherein the weight ratio of alcohol to adduct is in the range of from about 0.5:1 to about 0.65:1. 
     
     
       9. The process of claim 8 wherein the alcohol is comprised of about 90 weight percent n-propanol and about 10 weight percent t-butanol. 
     
     
       10. The process of claim 9 wherein the sulfur halide is sulfur monochloride and the olefin is isobutylene. 
     
     
       11. The process of claim 1 wherein the weight ratio of lower alkanol to adduct is in the range of from about 0.5:1 to about 0.65:1. 
     
     
       12. The process of claim 1 wherein the lower alkanol is comprised of about 90 weight percent n-propanol and about 10 weight percent t-butanol. 
     
     
       13. The process of claim 1 wherein the sulfur halide is sulfur monochloride. 
     
     
       14. The process of claim 1 wherein the olefin is isobutylene.